Skin lightening compositions and methods

Abstract

Skin lightening/even toning compositions are provided for reducing skin pigmentation of normal skin and for lightening hyper-pigmented skin said compositions comprising (i) highly purified hexylresorcinol which is substantially free or resorcinol, (ii) optionally, at least one other skin lightening agent, and (iii) a dermatologically acceptable carrier.

1 . A skin lightening/even toning composition for preventing or lessening pigmentation of normal human skin or of hyper-pigmented human skin said composition comprising (i) a skin lightening effective amount of highly purified hexylresorcinol, (ii) optionally, from about 0.01 to about 20 weight percent of at least one other skin lightening agent, and (iii) a dermatologically acceptable carrier, wherein said hexylresorcinol has a purity of at least 96 wt % and is free or substantially free of resorcinol. 
   
   
       2 . The skin lightening/even toning composition of  claim 1  wherein the highly purified hexylresorcinol is free or substantially free of resorcinol and has a purity of 99% weight percentage. 
   
   
       3 . The skin lightening/even toning composition of  claim 1  wherein the said highly purified hexylresorcinol contains resorcinol less than 0.1 weight %. 
   
   
       4 . The skin lightening/even toning composition of  claim 1  wherein the said highly purified hexylresorcinol is present in an amount of from about 0.05 to about 10 percent by weight. 
   
   
       5 . The skin lightening/even toning composition of  claim 1  wherein the second skin lightening agent is present and the weight ratio of the highly purified hexylresorcinol to the second skin lightening agent is from 20:1 to about 1:20. 
   
   
       6 . The skin lightening/even toning composition of  claim 1  wherein the highly purified hexylresorcinol is present in an amount of from about 0.1. to about 5 wt %, the second skin lightening agent is present in an amount of from about 0.1 to about 5 wt%, and the weight ratio of the highly purified hexylresorcinol to the second skin lightening agent is from about 10:1 to about 1:10. 
   
   
       7 . The skin lightening/even toning composition of  claim 6  wherein the highly purified hexylresorcinol is free or substantially free of resorcinol and has a purity of 99% weight percentage. 
   
   
       8 . The skin lightening/even toning composition of  claim 1  further comprising one or more conventional skin protective or treatment ingredients in an effective amount. 
   
   
       9 . The skin lightening/even toning composition of  claim 1  wherein the additional ingredients are selected from the group consisting of sunscreen actives, antioxidants, vitamins, anti-inflammatory agents, moisturizers, emollients, humectants, and mixtures thereof. 
   
   
       10 . The skin lightening/even toning composition of  claim 1  wherein the second skin lightening agent is present and the skin lightening efficacy of the composition is greater than for a like composition containing just the second skin lightening agent in amount equal to the combined amount of hexylresorcinol and second skin lightening agent. 
   
   
       11 . The skin lightening/even toning composition of  claim 1  having improved color stability as compared to a like composition employing conventional hexylresorcinol or other phenolic based skin lightening agents. 
   
   
       12 . An improved skin lightening/even toning composition wherein the improvement comprises the presence of front about 0.01 to about 20 weight percent of a highly purified hexylresorcinol, said highly purified resorcinol having a purity of at least 99 wt % and being free or substantially free of resorcinol. 
   
   
       13 . The improved skin lightening/even toning composition of  claim 12  wherein the said highly purified hexylresorcinol is present in an amount of from about 0.1 to 5 percent by weight. 
   
   
       14 . The improved skin lightning/even toning composition of  claim 12  further comprising one or more conventional skin protective or treatment ingredients in an effective amount. 
   
   
       15 . The improved skin lightening/even toning composition of  claim 14  wherein the additional ingredients are selected from the group consisting of sunscreen actives, antioxidants, vitamins, anti-inflammatory agents, moisturizers, emollients, humectants, and mixtures thereof. 
   
   
       16 . The improved skin lightning/even toning composition of  claim 14  wherein at least one of said additional skin protective or treatment ingredients is one or more sunscreen actives. 
   
   
       17 . A method of lightening skin color, said method involving the step of applying a skin lightening/even toning composition comprising (i) a skin lightening effective amount of highly purified-hexylresorcinol (ii) optionally, from-about 0.01 to about 20 weight-percent of at least one other skin lightening agent, and (iii) a dermatologically acceptable carrier, wherein the said highly purified hexylresorcinol is free or substantially free of resorcinol and has a purity of at least 96 wt%, to the areas of the skin to be lightened. 
   
   
       18 . The method of  claim 17  wherein the skin lightening composition is applied to the areas to be treated in an amount sufficient to provide a light coating to the skin at least twice a day until the desired skin lightening effect is achieved. 
   
   
       19 . A method of preventing skin darkening due to environmental or physiological conditions, said method involving the step of applying a skin lightening/even toning composition comprising (i) a skin lightening effective amount of highly purified hexylresorcinol (ii) optionally, from about 0.01 to about 20 weight percent of at least one other skin lightening agent, and (iii) a dermatologically acceptable carrier, wherein the said highly purified hexylresorcinol is free or substantially free-of resorcinol and has a purity of at least 96 wt %, to the areas of the skin to be lightened. 
   
   
       20 . The method of  claim 19  wherein the skin lightening composition is applied to those areas subject to conditions that otherwise are likely to induce skin darkening.